1. Field of the Invention
The present invention relates generally to the field of band saws and more specifically, those saws used to sever runners or stringers from deck boards of a pallet or skid.
2. Description of the Prior Art
Wooden pallets or skids become damaged through continued use and particularly as a result of contact with the forks of forklift trucks. Wooden pallets have a plurality of parallel top deck boards and bottom deck boards spaced apart but secured together by wooden runners that extend crosswise relative to the deck boards. The deck boards and runners are secured together by conventional fastening devices, such as by nails. Typical pallet damage occurs when the runner located at the end of the pallet is split or otherwise damaged by the lifting device. A solution is to insert a new runner between the deck boards while fastening the new runner inwardly of and to the damaged runner. The pallet is therefore structurally sound; however, the amount of space between the added end runner and the runner which extends at the midway point across the pallet or to the runner located at the opposite end of the pallet is reduced. Certain robotic machines have lifting arms spaced apart to fit exactly into the pallet between the original undamaged runners. As a result of the aforementioned repair technique of inserting an additional runner, the amount of space between runners is reduced and thus such a pallet does not allow certain robotic lifting arms to be inserted therein. Pallets are therefore classified according to whether or not a pallet has been damaged or repaired as described. For example, the value of a pallet that is not damaged typically may be $5.00 to $5.50 each whereas a pallet that has been damaged but repaired by the addition of an additional interior runner has a worth of only approximately $1.50 to $2.50 each. The aforementioned repair technique therefore has serious financial consequences.
It is therefore desirable to completely remove the damaged runner from the pallet in a cost effective manner. One technique is to utilize the band saw disclosed in our U.S. Pat. No. 6,128,992 wherein a pair of band saws simultaneously sever the fasteners securing the opposite deck boards to the runners. In lieu of utilizing a pair of band saws along with the associated drive mechanisms, it is desirable to provide a device having a single band saw wherein the saw may be used to sever the fasteners securing the bottom and top deck boards to the runner. Disclosed herein is such a saw supported for movement above a table allowing the pallet to be pivoted by a single operator enabling the same saw to be used for severing the bottom deck board fasteners as well as the top deck board fasteners.
U.S. Pat. No. 5,323,525 issued to John L. Johnson discloses a cutter head for a pallet dismantling machine. In many cases, round disc type pallet dismantlers cause damage to the deck boards and leave nail stubble. Additional techniques, include a common band saw used to saw into the pallet between the end runners and deck boards with the pallet then being pulled backwards, the pallet flipped over and the opposite deck boards then being sawed from the runners. A problem develops when the pallet is pulled backwards to extricate the saw blade from within the pallet since the saw blade teeth are on the trailing edge of the saw as the saw is moved from the pallet.
One embodiment of the present invention is a saw for removing a runner of a pallet with the pallet having top deck boards and bottom deck boards secured to the runner by fasteners The pallet has a normal horizontal position, an upside down horizontal position and when on end a vertical position. A table has a table surface for supporting the pallet in the normal horizontal position and further has a stop surface beneath the table surface for supporting the pallet when on end in a vertical position. A band saw is movably mounted to the table and has teeth movable across the table surface. The band saw is located a first distance apart from the table surface for severing fasteners holding bottom deck boards to a runner of the pallet as the pallet is moved in a forward direction past the saw. The band saw is located a second distance greater than the first distance apart from the stop surface allowing the pallet to be pivoted to a vertical position and then to an upside down horizontal position while the saw remains within the pallet between the deck boards enabling the pallet to be pulled in the forward direction severing fasteners securing the runner to the top deck boards.
Another embodiment of the present invention is a method of removing a damaged runner secured by fasteners to top deck boards and bottom deck boards of a pallet. The method includes the step of providing a device with a pallet supporting surface, a stop surface spaced from the supporting surface and a saw movable across the pallet supporting surface. The pallet is positioned upon the supporting surface and aligned with the saw so the saw passes between the bottom deck boards and the runner severing the fasteners. The pallet is pivoted upon the stop surface to an upside down position while the saw remains within the pallet between the top deck boards and the bottom deck boards. The saw then passes between the top deck boards and the runner.
It is an object of the present invention to provide a new and improved method and device wherein the fasteners securing top deck boards to a pallet runner and the fasteners securing the bottom deck boards to the pallet runner are severed enabling a damaged runner to be removed.
It is an object of the present invention to provide a table band saw for severing fasteners holding bottom deck boards to a runner when the pallet is moved in a first direction and then for severing fasteners holding the top deck boards to the pallet runner after the pallet is pivoted upside down and moved past the saw in the first direction.
A further object of the present invention is to provide a new and improved method for removing a damaged runner secured by fasteners to top deck boards and bottom deck boards of a pallet.
Related objects and advantages of the present invention will be apparent from the following description.